NGS, Liquid Biopsy Combined to Detect Specific Mutation in NSCLC

Two technologies—next-generation sequencing (NGS) and liquid biopsy—are combined in one diagnostic test to help guide treatment decisions for patients with a particularly deadly form of advanced lung cancer.

It is the first such approval for a diagnostic like this, the FDA said, calling it “a new era for mutation testing.”

The test is for patients with specific types of mutations of the epidermal growth factor receptor (EGFR) gene in metastatic non–small cell lung cancer (NSCLC).

“In addition to benefitting from less invasive testing, patients are provided with a simultaneous mapping of multiple biomarkers of genomic alterations, rather than one biomarker at a time, which can translate to decreased wait times for starting treatment and provide insight into possible resistance mechanisms,” Tim Stenzel, MD, PhD, director of the Office of In Vitro Diagnostics and Radiological Health in the FDA’s Center for Devices and Radiological Health, said in a statement.

The approval was granted to Guardant360CDx to provide information on multiple solid tumor biomarkers and to help identify EGFR mutations in patients who will benefit from treatment with osimertinib (Tagrisso), which is approved for a form of metastatic NSCLC.

Osimertinib was granted Breakthrough Therapy Designation from the FDA last month for EGFR-mutated NSCLC, following surgery for completely tumor resection. Likewise, the Guardant360 CDx assay was granted a Breakthrough Device Designation as well.

A liquid biopsy uses a blood sample to uncover genetic information about a tumor and can be used where standard tissue biopsies are not feasible, such as tumor location. The NGS technology in the assay uses high-throughput tumor profiling and can simultaneously detect mutations in 55 tumor genes, rather than 1 gene at a time.

The FDA also clarified when a biopsy should be performed.

“Genomic findings for other biomarkers evaluated are not validated for choosing a particular corresponding treatment with this approval,” the FDA said. “If the specific NSCLC mutations associated with today’s approval are not detected in the blood, then a tumor biopsy should be performed to determine if the NSCLC mutations are present.”

The Guardant assay was the second of 2 such approvals by the FDA last week. Earlier in the week, the FDA approved clonoSEQ, made by Adaptive Biotechnologies, for its third indication to detect minimal residual disease, this time in chronic lymphocytic leukemia.